This application claims the benefit of German patent application 10007950.4 filed Feb. 22, 2000, herein incorporated by reference.
The present invention relates to a device for starting a work station of a cheese-producing textile machine, especially after a batch change, and relates more particularly to such a device wherein the work station has a creel for rotatably holding a bobbin tube on which a cheese of yarn is to be wound from a feeding bobbin or cop, a splicing or yarn connecting device for connecting yarn ends form the cheese and the cop, and manipulating means for inserting the yarn ends into the splicing device, for example a gripper tubes or other like devices for inserting a trailing yarn end from the cheese and a leading yarn end from a feeding cop into a yarn clamping and cutting device arranged in the area of the splicing device.
In connection with the operation of cheese-producing textile machines, in particular automatic cheese winders, it is customary in case of a yarn break or a change of the feeding bobbin to initially activate an automatic yarn splicer or like yarn connecting device via a computer associated with the respective bobbin winding head, as described, for example, in German Patent Publication DE 40 05 752 A1. More specifically, a suction nozzle is first placed into contact with the surface of the upper winding bobbin, also referred to as a cheese, which slowly rotates opposite the normal winding direction, in order to unwind a length of the trailing yarn end from the cheese to be aspirated into the suction nozzle. After the upper yarn end from the upper cheese has been grasped, the suction nozzle is pivoted back into its initial position, in which the suction nozzle opening is positioned below a splicing device. In the process, the section of yarn extending between the cheese and the suction nozzle is pulled into an electronic cleaner arranged above the splicing device and into a clamping and cutting device positioned in this area and, also is guided by appropriate guide contours of yarn guide plates and yarn guide hoops, into the cutter portion of a cutting device located below the splicing device.
Almost simultaneously with the suction nozzle, a gripper tube, which is positioned in a lower initial position, pivots into an upper work position and in the process brings along a leading end of the bottom yarn from the feeding bobbin, also referred to as a cop, which theretofore had been drawn off the cop and had been held in a yarn tensioner. In the course of the gripper tube pivoting into its upper work position, the leading end of the bottom yarn from the cop is also guided by appropriate yarn guide contours and slides into an opened yarn clamp, as well as an opened cutting device. Subsequently the upper and lower yarn ends are cut to the correct length, are prepared in so-called opening tubes and are connected with each other in the splicing device.
Accordingly, an upper yarn brought downwardly from the cheese and a lower yam brought upwardly from the feeding cop are always needed in order to be able to automatically continue the operation at the work stations of an automatic cheese winder, for example after a yam break. Likewise, when a fully wound cheese is to be replaced with an empty bobbin tube, it must be correspondingly assured that the bottom yarn from the feeding cop extends sufficiently into the area of the empty cheese tube held in the creel of the respective work station so as to be fastened on the empty tube.
In bobbin winding machines which have an automatically operating service traveler, generally called a cheese changer, it is known (e.g., from German Patent Publication DE 195 33 833 A1) that, in case of a cheese/empty tube change, the yarn still tensed between the feeding cop and the finished cheese is initially picked up by a special manipulating device of the service traveler, a so called yarn lifter, and is severed by cutting and clamping elements arranged on the yarn lifter. In the process the yarn end from the feeding cop is retained and is subsequently placed against the new empty tube positioned in the creel.
It is furthermore known, for example from German Patent Publication DE 24 63 461 C2, to respectively install a separate clamping and cutting device dedicated to the bobbin winding head in the area of the creel of each individual work station which, in case of a cheese/empty tube change, fixes the yarn in place prior to ejecting the cheese so that thereafter the yarn is ready to be placed against a new empty tube.
However, the above described devices have the disadvantage that they are ineffective in case of a batch change, i.e. when the yam material is changed in a bobbin winding machine and the appropriate new feeding cops are brought into the work stations. In such batch changes, it will therefore be understood that neither an upper nor a bottom yam will be present to start each work station. Therefore, a manual intervention by the operators has always been required heretofore in the case of a batch change in order to start up every individual bobbin winding head.
Based on the above mentioned state of the art, it is an object of the present invention to further improve the known work stations of cheese-producing textile machines.
This object is attained in accordance with the present invention by means of a device having the particular advantage that, after a batch change, the individual work stations of the cheese-producing textile machines can be automatically returned to operation without any manual intervention by the operators. Thus, not only is the length of time for restarting the automatic cheese winder considerably shortened in this manner, and therefore the efficiency of the respective textile machine clearly increased, but the workload of the operators is also noticeably relieved.
In a preferred embodiment, the device has an additional suction tube, defined by a stepper motor and pivotable from a yarn pick-up position into a yarn transfer position. This suction tube, which can be charged with a vacuum, automatically picks up the yarn end which previously had been brought from the gripper tube to the splicing device and had been cut by a cutting device arranged thereat, and which then lies on an interim location of deposit, i.e. a deposit plate, and transports it to a clamping and cutting device arranged in the area of the cheese creel, which subsequently makes the yarn available for transfer to the empty tube.
Further details, features and advantages of the present invention will be understood from an exemplary embodiment described below with reference to the accompanying drawings.
FIG. 1 is a schematic lateral view of a work station of an automatic cheese winder with a device in accordance with the present invention, and
FIGS. 2 to 6 sequentially represent the individual process steps when employing the device in accordance with the invention.